Clutch replacement time

The clutch parts for my CGT arrived yesterday, so I can no longer put off
the replacement. I have the car up un ramps, wheels chocked, etc. I was
surprised to see that on the warning label of the ramps, it said that it was
unsafe to use them if the tranny was going to be removed. Why is this? The
suspension is still in place, so the wheels will not move. I have some
jackstands in place also under the reinforced frame area as backup, so do
you think it would be OK to still use the ramps? Now onto getting the tranny
out. Bentley actually is no better than the cheapy Haynes manual on this
procedure. First, why does the airbox need removed? I know the engine will
move a bit when the tranny comes off, but if I pull the hose connecting the
two, why would it need to come off? I had a hell of a time just replacing
the filter element (had to remove the bumper trim, headlight and grille, and
barely then would the air filter slip into place). Second, the exhaust
downpipe needs to be removed. I was looking at the bolts attached to the
studs from the exhaust manifold, and they look very rusty. I have a feeling
trying to remove these bolts will result in snapped studs, despite a liberal
soaking in some PB Blaster, etc. Any way around this step (its a FWD, so no
driveshaft comes out of the rear of the tranny)? TIA.
Craig
'92 100S (91k)
'86 CGT (195k)